ceph/src/boost/libs/preprocessor/doc/ref/variadic_elem.html

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   7 <div style="margin-left: 0px;"> The <b>BOOST_PP_VARIADIC_ELEM</b> variadic macro
   8 extracts an element from <i>variadic data</i>. </div>
   9 <h4>Usage</h4>
  10 <div class="code"> <b>BOOST_PP_VARIADIC_ELEM</b>(<i>i</i>, <i>...</i>) <a href="../topics/variadic_macros.html#VNotation" target="_self"><sup>(v)</sup></a><br>
  11  </div>
  12 <h4>Arguments</h4>
  13 <dl><dt>i</dt>
  14   <dd> The zero-based index into the <i>variadic data</i> of the element to be
  15 extracted.&nbsp; Valid values range from <i>0</i> to the size of the variadic data - 1.
  16   </dd>
  17   <dt>...<br>
  18 </dt>
  19   <dd> The <i>variadic data</i> from which an element is to be extracted. </dd>
  20 </dl>
  21 <h4>Remarks</h4>
  22 <div>The index <i>i</i> must be less than the size of the <i>variadic data</i>. </div>
  23 <h4>See Also</h4>
  24 <ul>
  25   <li><a href="limit_variadic.html">BOOST_PP_LIMIT_VARIADIC</a></li>
  26 </ul>
  27 <h4>Requirements</h4>
  28 <div> <b>Header:</b> &nbsp;<a href="../headers/variadic/elem.html">&lt;boost/preprocessor/variadic/elem.hpp&gt;</a>
  29 </div>
  30 <h4>Sample Code</h4>
  31 <div>
  32 <pre>#include &lt;<a href="../headers/variadic/elem.html">boost/preprocessor/variadic/elem.hpp</a>&gt;<br><br>#define VAR_DATA a, b, c, d<br><br><a href="variadic_elem.html">BOOST_PP_VARIADIC_ELEM</a>(0, VAR_DATA) // expands to a<br><a href="variadic_elem.html">BOOST_PP_VARIADIC_ELEM</a>(3, VAR_DATA) // expands to d<br></pre>
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  35 <div style="margin-left: 0px;"> <i></i><i>© Copyright Edward Diener 2011,2013</i> </div>
  36 <div style="margin-left: 0px;">
  37 <p><small>Distributed under the Boost Software License, Version 1.0.
  38 (See accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a>
  39 or copy at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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